1. Field of the Invention
The present invention generally relates to a navigation route calculation method in mobile navigation systems or internet navigation systems providing services where a method is employed to calculate routes with the lowest energy consumption. Calculating routes based on the lowest energy consumption may result in saving energy even if a selected route may have a longer distance or may take a longer time than another route.
2. Description of the Related Art
Today's mobile navigation systems contain map information stored on a local storage system, (hard disk, flash memory, etc.), and offer a user interface driven by local software to calculate the route from a specified start point to a specified target destination. These navigation systems dynamically navigate the user to the target destination using GPS signals to calculate the user's current position.
Mobile navigation systems and network computer-based navigation systems contain map information typically stored on a mobile navigation system's local storage or in a networked computer database. A user typically interacts via a software driven user interface to enable selection and calculation of a route from a specified origination location to a specified target destination.
During the process of calculating a route, the navigation system typically determines a number of alternative routes before displaying the selected route to the user. Alternatively, the navigation system predetermines which intermediate routes may be used to calculate the final route based on certain user selected parameters that affect total time and total distance values in determining a route.
The user influences the calculation method by determining a route typically based on the shortest travel time, the shortest route, or a combination of these two options, i.e., an “optimized route” including both features of travel time and distance. Typically, navigation systems may select a navigation route based on one of these three options depending on a user selected means of travel, i.e., the route is to “optimized” for automobiles, commercial vehicles, cyclists, pedestrians, etc.
To calculate a potential route, a navigation system determines the overall distance by individually determining the distance of each individual section of the route. Each individual route section represents a general type of road, e.g., highway, country road, inner city, etc.
These “road types” have specific characteristics which influence the route calculation, and selection based on average speed and limitations regarding specific vehicles, etc.
However, the prior art has not shown any capacity to select a navigation route based on estimated energy consumption factors affecting fuel economy that a traveler may encounter, for example, the grade of particular portions of road in a route, or the number of stops or potential delays in a route.